eTunes (i.e. easyTunes) is a small application that allows even non-professional musicians to create and play their own tunes.
In fact it is enough to click the piano-keys and eTunes will take care to code your inputs for the right output.
eTunes does NOT create files to be played by other applications like iTunes: it can play only its own files. To create audio-files the user will have to take advantege of other applications (like GarageBand).
A Tutorial and several songs are offered to help the user create chords and more complex music.